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arXiv · 1404.0593

Highly efficient generation of single-mode photon pairs using a crystalline whispering gallery mode resonator

Michael Förtsch·Gerhard Schunk·Josef U. Fürst·Dmitry Strekalov·Thomas Gerrits·Martin J. Stevens·Florian Sedlmeir·Harald G. L. Schwefel·Sae Woo Nam·Gerd Leuchs·Christoph Marquardt
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Abstract

We report a highly efficient source of narrow-band photon pairs based on parametric down-conversion in a crystalline whispering gallery mode resonator. Remarkably, each photon of a pair is strictly emitted into a single spatial and temporal mode, as witnessed by Glaubers autocorrelation function. We explore the phase-matching conditions in spherical geometries, and determine the requirements of the single-mode operation. Understanding these conditions has allowed us to experimentally demonstrate a single-mode pair-detection rate of $0.97 \cdot 10^6$ pairs/s per mW pump power per 20 MHz bandwidth without the need of additional filter cavities.

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Michael Förtsch, Gerhard Schunk, Josef U. Fürst, Dmitry Strekalov, Thomas Gerrits, Martin J. Stevens, Florian Sedlmeir, Harald G. L. Schwefel, Sae Woo Nam, Gerd Leuchs, Christoph Marquardt. 2014-04-02. Highly efficient generation of single-mode photon pairs using a crystalline whispering gallery mode resonator. https://doi.org/10.1103/physreva.91.023812

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